For the treaty trader visa, the trade between the US and the foreign country must make up the majority of the foreign trade. Finally, there must be a pattern of systematic trade which shows that there is a steady volume of trade.

For the E-2 visa, the investment made into the US corporation must be substantial. There is no set investment required as every entity and set up are different, but it must be a substantial. Next, the investment funds must be placed a risk which means that you cannot just have them sitting in a bank account and expect the visa to be issued. Finally, the investment cannot be marginal which means that there should be income for US employees and maybe even a profit.